As far as I know there are no programs that will give you a 100% conversion without some manual touch up. I found it was easier to scan what you want insert the scan directly into CAD, scale it, and trace over the underlay. On bulkheads and frames etc you only have to trace half and mirror the other side. This way you can correct any errors in the original.
Don

Doug,
Speeds and feeds for milling whether manual or CNC can be tricky. It depends on many factors material, bit size, spindle speed, feed rate and the bit type (carbide, HSS, number of flutes) whether drill, end mill etc. and chip clearance. Check out some speed and feed calculators online to give you some ideas.
The the short answer for the slower rpm is you can use HSS bits to cut hard material such as stainless or tool steel. If you switch to a carbide bit you can increase your spindle speed and feed rate without burning up the bit and get a good finish. In our hobby work we usually work with softer materials such as wood, brass, plastic etc. so the slower speeds aren't as important. You also have to keep in mind many of these calculators may assume you are using a coolant which you will not be using.
A easy visual of this is using a hand router. Move the router to fast it starts tearing out and leaves a rough surface, to fast and you burn the wood and bit.
Keep in mind we are doing this for a hobby to have fun. In the end you will probably use the higher end of the spindle speed with some carbide bits and adjust you feed rate to match.
Don

Doug,
EMC2 and Linux are open source software, you should be able to upgrade to a newer version without any cost. I am not real familiar with either thou but I am sure an Internet search would give you all the info needed. I use mach3 for my control software which is windows based and very popular with hobby and small shops. The important thing about both programs is they are based on old hardware platforms specifically the 25 pin parallel port. An old computer with the parallel port on board is an advantage. If you use a newer computer with no parallel port you will need to convert the USB signal to pulse signal for the 25 pin parallel port that goes to the stepper drivers. The timing of these signals is what allows you to control direction and speed in all directions at the same time. You would think that it would as easy as using an USB to parallel converter but it's not. You need special converter or a separate breakout board (such as smooth stepper). Also just sticking in a parallel card in the computer is a hit and miss, I don't know about the new Linux platforms but the new Windows OS do not support parallel ports the way the old OS did. Whether you have an box that plugs directly into an USB or an Ethernet port all of the stuff I just mentioned is built into the box. From that hardware, whether in a separate box or built into a computer, this is what you connect your stepper cables to.
You do not need a new processor to run these programs. I use an old Pentium 4 with Windows XP that is over 10 years old. Will I have to eventually upgrade, yes but not until this computer dies. The main reason is that I would have to buy a USB motion control breakout box and reload and setup up the software.
Yes you can use a CNC machine manually. There are a number of ways: handles on the stepper shaft,. keyboard, joystick, and a pendant (MPG (manual pulse generator)). A pendant is the easiest. All the axis, speeds, steps etc. can be controlled by this hand held unit.
What also is important is the spindle speed. Getting something up to 10000 rpm is nice especially since you will be using smaller cutters.
I should say I don't own the Sherline I have a Taig CNC mill, but all these hobby type CNC machine are all basically the same. They use steppers, stepper drivers, control software (almost alway EMC2 or mach3), and a PC. You also need software to draw you part and software to generate g-code. Note Fusion is free for non commercial use.
I am by no means an expert. My son has his own small engineering and CNC manufacturing business, so when he needs the extra help I operate one of the large mills (these are not hobby mill but the principle is the same) so this gives me some practice at what not to do. If I get in trouble I just find him that's the nice thing about being free help, but I have learned a lot by helping and watching him trouble shot.
Don

Joe
Generally what they mean by CNC ready is that the machines are ready to attach the stepper motors. In short the brackets are attached to the machine and you need the stepper motors mounted to be able to use the machine in any mode. The handles attach to the shaft on the back of the stepper, then you would be able to rotate the shaft as if in manual mode. To run in CNC mode you need to attach the steppers to drivers then this controller box is attached to a computer with the controller software (the most common is probably Mach3). This is how almost all hobby CNC mills are controlled. Some setups use servo motors and ball screws but this setup is not as common for hobby use because of expense, but there are some out there. Servo motors are used in commercial machines because they provide position feedback (the machine always knows where it's at) stepper motors do not.
The easiest way to use a CNC mill in manual mode is to have the machine able to function in CNC mode. Then use a pendent to move the axis and use the controller software as a digital readout. This way you have a fully functional machine in both modes.
I will try to get some pictures of my Taig setup (the setup is similar no matter what brand machine you use) this weekend. It is partially tore down as I am designing an enclosure for it. It is easier to explain if you have something to look at.
Take a a look at this build log he uses a Taig setup very similar to mine. He has a great log and this will give you a very good idea of what can be done with a good hobby CNC mill. Hopefully this link works if not just do a search
http://Western River Steamboat Heroine by ggrieco - Scale 1:24 - 1838 as she appeared before hitting a snag in the Red River. - Build Logs for SCRATCH SHIP MODEL PROJECTS - Nautical Research Guild's Model Ship World
Don

I have a Taig CNC mill, the CNC machines have a bigger motor than the manual mill and also can run up to 10000 RPM. I believe you can have them put the larger motor on the manual machine. The Taig mills are a little bigger and heavier than the Sherline. The most common accessories like tilt table and the rotary table can be adapted for use on the Taig. I have the Sherline rotary CNC table and use it with the Taig. There are some differences in the manual and CNC versions of the Taig mill so look carefully if you compare the two.
I agree with Jim on the 3 flute end mill. My some son has his own custom machining and engineering business and he uses 3 flute end mills most of the time. With these you can get a smooth cut while being able to clear the chips. We also only use carbide.
Like most have said you can mill something small on a large machine but not the other way around. That being said I have a Taig mill and lathe, the lathe I have set up for CNC or manual operation and a Unimat 3 that I have most of the accessories. These are the machines I have set up where I work on model building. I also have at my disposal my sons equipment which includes 2 VMC machines the large one comes in at about 13000 lbs and the smaller one at about 10000 lbs. A bit of over kill for modeling to say the least.
The point being, I really never use any of the big equipment for modeling purposes I can get more than acceptable results for modeling from these small machines. The only time I use the larger equipment is for making something for the smaller machines (like a tooling plate). The important thing is keeping the working parts clean and maintained. Accuracy is only as good as the setup and aligning of the machine itself. These small machines can be extremely accurate if set up properly. An example in how accurate some of these small machines can be; I did the final op for 10 custom cam parts for my kids business over the weekend. We needed to get the total runout and one final dimension tolerance of 0.0005" I was able to do it with my Unimat 3 which is over 30 years old. I only had to take off 0.005", it took longer to do the setup than turn the parts. The catch is the entire part was milled in one in the large VMC mills except for one dimension he left 0.005" oversized. He milled 12 parts in a couple of hours (couple of extra if I screwed up and I did scrap one) it took me 4 hours to set and turn off the final 0.005". But on the small manual lathe I was able to set up multiple test indicators to guarantee that each part was in spec before we shipped. This is something we DON'T do on a regular bases, but gives an example of accuracy and capability of a good small machine. If we had to do these parts on my small equipment both my son and I would be able to collect social security before we finished.
The above example is way past what would ever be needed for any ship modeling. So pick a machine that fits your space, budget and needs. Then add in the tooling and accessories which will be as much as the machine. Sherline, Taig or a good Chinese machine would work for the small work required for modeling also at least 5000 RPM if able. Doing anything bigger than that, then a machine that is heavier and more ridged is better.
Somewhere on the sight in scratch builds, a guy uses a Taig CNC mill to do some fantastic stuff I can't remember which log though it's worth a look if you can find the log.
Don

Jud
Yes with a little tweaking of the drawings I could probably come up with a Baltimore class hull. The Baltimore’s were only about 40 feet shorter and 6 foot narrower than the Des Moines class. The hull shape though is almost identical. If you sat the 2 different model hulls next to one another about the only difference would be the length.
Bob and Nils
Yes that is a custom built table just for this model. The risers under the hull are milled for certain spots along the sheer line and screwed to the deck. Then I screwed the risers to the table which resulted in the keel being parallel to the table. I did all this so I could use the table as a reference when marking out for the bilges, armor plates, shafts etc.
Nils - Sitting is more of a necessity after I busted up my ankle a while back. I can’t stand for a long period of time before it hurts to a point were walking from one room to the next is difficult.
Don

David Most if not all of the hardware and fittings will be scratch built, a few exceptions my be some photo etched stuff from The Floating Drydock. The problem with this particular ship is that there was only three in the class; the Des Moines, Salem, and the Newport News. The Des Moines and the Salem were use as flagships for the Sixth Fleet and the Newport News was used as a flagship for the Second Fleet. The Newport News heavily modified and served into the Vietnam War, the Des Moines and the Salem were decommissioned around 1960 or so. It is much easier to find good plans and information on the Baltimore class as there were many ships built in that class and many had lengthy service. Luckily though the USS Salem CA 139 is a museum ship in Boston. There are many photos os her on the net which is a great help, I am not sure I could build a decent replica without those photos. When my dad was in the Med he said for a short peroid of time both the Salem and Des Moines were there together and was on both ship. He said they were almost identical except for a few compartments so I am confident that using those photos for reference will get me close enough. Don

Thanks all for the likes
Hopefully by starting this log it will keep me on track and moving along. This one project I want to keep moving and not drag on any longer than necessary. One my dad isn't getting any younger and two I want to get this beast out of my shop. I don't mind working on larger models but this one at times is a bit much. As I get the hull more complete I will be able to work on smaller sections at a time. This will help by having less moving around just to get one row of planks from the bow to the stern.
Once I get it flipped over and start working on the superstructure there will be more to show not just the boring planking and sanding and more sanding.
Don

Hi Ben
I have a 24x26 shop for woodworking and have basically the same equipment you do. I am on my second dust collector which is a 1.5 HP single stage, this works fine for what I use it for. I don't do as much woodworking as I used to so this works just fine. If I get another one I would probably go with a smaller cyclone type collector they are more efficient and easier to empty, especially if you do a lot of planing which creates lots of chips.
For my modeling area which is in the house I use a Fein dust extractor which I just love. It is quiet and variable speed but more expensive than the typical shop vac. It is so much quieter than a shop vac which is great for inside the house. The dust deputy basically turns it into a two stage system catching almost all the dust and debris before getting to the vac keeping the filter cleaner and easy to empty.
Don

Thanks all
After the last few years I am very excited getting back at it. I have a very supporting wife which helps a lot. I now leave the cell phone in another room and just check occasionally to see if someone actually needs me. I personally think they are highly overrated maybe I am just getting old and cranky. That seems to be the consensus of the kids.
Don

Hi, I was a member of MSW; signed back up for MSW 2 but life got in the way of rebuilding my log on the new site. Well in the last 2-3 years; I have had both my kids finish college, get married (both within 2 months of each other - talk about a stressful experience). My daughter and her husband are expecting their 2nd child and my son and his wife are expecting twins in March. Add a new computer system at work (working lots of overtime) and another surgery on my ankle. Throw all this together did not leave much time to work on hobbies. I do follow some logs and topics though to keep updated.
The current project I have been working on is the USS Des Moines CA 134. My dad served on this ship in 1958-59 so this goes to him when complete. I started log as I finally got some time to organize the pictures and put some text together.
My other two projects are on hold (for the most part) until I get this one done. My other two projects are Model Shipways Armed Virginia Sloop (replacing almost all of the wood from the kit) and a scratch 1:32 model of Chucks Syren.
Projects on Hold
Arm Virginia Sloop (Model Shipways)
Scratch build of Syren 1:32

The USS Des Moines class heavy cruiser was the largest heavy cruiser ever built. It is similar to the Baltimore class except bigger and only 1 stack. The main difference is the Des Moines class has automatic 8” guns using an encased powder. These guns did not use bagged powder that was normally used in guns this large. The guns were capable of about 12 rounds per minute per barrel compared to the Baltimore class at about 6 rounds per minute.
I am building this model for my dad which served on this ship from 1958-59 and has always wanted a model. I am finally getting enough time to give it a good go so hopefully it will all work out. The model is large about 88 inches (around 7.5 feet). Even at that size the scale is relatively small compared to the scale we traditionally build wooden ships. The reason I choose this scale is because I just hate working in a smaller scale than this. So he had a choice this big or no model at all.
The first thing in starting the model was get some plans, most came from the Floating Dry Dock some time ago, scan them and inserted into CAD. It took a while to get them all sized and aligned properly. After doing that I found many errors in some of the drawings that took some time to get corrected.
I then worked on getting the false keel and bulkheads printed out and cut up. The bulkheads that I had reliable information on and was fairly certain were correct; this was not a large enough number to make a sturdy hull. I then had to work backwards after that to get the shape of the remaining bulkheads. I did this by drawing in two bulkheads in between the ones I was certain of. I did all the drawings in CAD; this was a trial and error type of process that took some time. I then print them out, made a foam board template, temporary gluing them in place and started fairing them out. After I got some faired out I then used them as a pattern and cut out the bulkheads in plywood and glued in place. I started at the stern and worked my way up to the bow. I used ¼” Baltic birch plywood for both the keel and bulkheads. This was a fairly lengthy process but I am real happy with the results so far.
I am presently working on the planking which is going along at a steady pace, just a lot of it. The planks are fastened to the bulkheads with glue and pin nails using an air nailer. It works great for this as it will all be filled and covered with a polyester resin. I am using 1/16” wood for the planking, mostly basswood but some beech was used also. I had some leftover beech so I used what I could on this then switched to basswood which I have a lot of. It does not matter what wood is used it will all get covered and painted. I am hoping to finish the planking sometime after the first of the year.
Basic starting point
Template process
working my way forward with making new bulkheads
Bulkheads and reinforcing the keel complete, just for size comparison the Arm Virginia Sloop sitting on top
Planking to this point
Don

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